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Motorcycle Catalyst Test Facilitv

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					Motorcycle Catalyst Test Facilitv
                    J                            J                                      J

JOHNSON MATTHEY EVALUATES CATALYSTS FOR ENGINE EMISSIONS
  Since the Taiwanese environmentalprotection              catalysts for 2-wheelers, Johnson Matthey has
agency introduced legislation requiring the use            installed a chassis dynamometer in its European
of catalysts on 2-stroke motorcycles in 1992,              Autocatalyst Technology Centre located at
many other regions have considered employing               Royston, England. From February 1999, the
stricter emissions requirements. EC regulations            facility will be able to test the full range of 2-
for enforcing the use of catalysts for mopeds will         wheelers, from mopeds to superbikes, over the
be implemented in June of this year, while in              various emissions test cycles in use in different
India most 2- and 3-wheeled vehicles will be fit-          parts of the world.
ted with catalysts from April 2000. This legis-              Many of the requirements for motorcycle cat-
lation has been drawn up as a result of the wide-          alysts, such as to be small, to have little effect
spread use of small motorcycles with 2-stroke              on engine power, to reduce high concentrations
engines. A 2-stroke engine produces relatively             of hydrocarbon and to withstand the large tem-
high levels of hydrocarbons and carbon monox-              perature rise across the catalyst that this causes,
ide although levels of NOx are low. In fast grow-          are different to the requirements for passenger
ing economies, such as those of India and China,           car catalysts. This test facility will enable cata-
small 2-stroke powered 2-wheelers of less than             lysts to be better tailored to the type of engine
200 cc are widely used as daily transport and              and vehicle, thus meeting legislation and achiev-
this has contributed to a serious urban pollution          ing good durability with little effect on vehicle
problem.                                                   power and costs.             R. D. O’S-AN
  Motorcycles using 4-stroke engines generally
produce lower levels of carbon monoxide and
hydrocarbons + NOx but may need a small
reduction in the amount of carbon monoxide
emitted in order to meet the conformity of pro-
duction regulations. This may be achieved by
using a cdtqlyst or by secondary air injection, for
instance. In response to the requirement for




An Indian Bajaj “Sunny Zip” 50 a? moped being tested
on the motorcycle chassis dynamometer a t the
European Autocatalyst Technology Centre in Royston.
The hack wheel of the bike rests on the dynamometer,
or rolling road, to which the load is applied; the
front wheel is clamped. The tester seated on the bike
follows the drive trace normally displayed on the
monitor in front of him, matching the bike’s speed to
the prescribed drive cycles. The exhaust system has
been cut away to show the position of the cylindrical
catalyst which is mounted in the silencer unit. The
exhaust gases from the bike are fed, via the white tube,
into a constant volume sampler. Here they are diluted
with air, before being fed into an emissions analyser,
to the left of the tester. The large blue fan placed in
front of the bike simulates the flow of air that would
occnr in normal use




Platinum Metals Rev., 1999, 43, (l), 13                                                                    13

				
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Description: Motorcycle Catalyst Test Facilitv